The chemical structure of tiotropium was first described in U.S. Pat. No. 5,610,163 and RE39,820. Tiotropium salts include salts containing cationic tiotropium with one of the following anions: bromide, fluoride, chloride, iodine, C1-C4-alkylsulphate, sulphate, hydrogen sulphate, phosphate, hydrogen phosphate, di-hydrogen phosphate, nitrate, maleate, acetate, trifluoroacetate, citrate, fumarate, tartrate, oxalate, succinate and benzoate, C1-C4-alkylsulphonate, which may optionally be mono-, di- or tri-substituted by fluorine at the alkyl group, or phenylsulphonate, which may optionally be mono- or poly-substituted by C1-C4-alkyl at the phenyl ring. Tiotropium bromide is an anticholinergic providing therapeutic benefits, e.g. in the treatment of COPD and asthma, and is the active ingredient in SPIRIVA (tiotropium bromide) HANDIHALER (dry powder inhaler) (Boehringer Ingelheim, Germany). Tiotropium bromide is known to crystallize in various forms, such as crystalline anhydrous (described e.g. in U.S. Pat. Nos. 6,608,055; 7,968,717; and 8,163,913 (Form 11)), crystalline monohydrate (described e.g. in U.S. Pat. Nos. 6,777,423 and 6,908,928) and crystalline solvates (described e.g. in U.S. Pat. No. 7,879,871). The various crystalline forms of tiotropium can be distinguished by a number of different assays, including X-ray Powder Diffraction (XRPD), Differential scanning calorimetry (DSC), crystal structure, and infrared (IR) spectrum analysis. Tiotropium can be synthesized using a variety of methods which are well known in the art (including, e.g. methods described in U.S. Pat. Nos. 6,486,321; 7,491,824; 7,662,963; and 8,344,143).